Instaseis Tutorial
Part 2: First Basic Exercise

Seismo-Live: http://seismo-live.org

## First Basic Exercise¶

Task: Calculate three component synthetic seismograms for the stations and events in the data/events and data/stations subdirectories and save them on disc.

#### Notes¶

1. Receiver objects can also be created from StationXML, SEED, or STATIONS files as well as obpy inventories using instaseis.Receiver.parse(); see the documentation for details.
2. Source objects can also be created from QuakeML, CMTSOLUTIONS, and in other ways using instaseis.Source.parse(); see the documentation for details.
3. The get_seismograms() method has a couple of extra arguments:

• kind: displacement, velocity, acceleration
• remove_source_shift, reconvolve_stf, dt,

... see the documentation for details.

4. You can use the properties of the Receiver and Source objects to create usefull filenames.

Basic lines to set up the notebook and some paths.

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%matplotlib inline
import matplotlib.pyplot as plt
import numpy as np
import os
import obspy
plt.style.use('ggplot')
plt.rcParams['figure.figsize'] = (10, 8)


Import Instaseis and open the database:

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import instaseis
db = instaseis.open_db("data/database")


reminder: you can use ObsPy to load stations and plot a map:

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from obspy import read_inventory

inventory.plot(projection="local", resolution="i");


This inventory can directly be used as input to generate a list of instaseis.Receiver objects:

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receivers = instaseis.Receiver.parse(inventory)
print(rec)


Alternatively, instaseis can directly open the station xml or STATIONS file (but then you don't have the nice plot):

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receivers = instaseis.Receiver.parse('data/stations/all_stations.xml')


reminder: use ObsPy to load events from a QuakeML file containing all events and plot a map:

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import glob # provides iterator to loop over files

cat = obspy.core.event.Catalog()

for filename in glob.iglob('data/events/quakeml/*.xml'):

print(cat)
print(instaseis.Source.parse(cat.events[0]))
cat.plot();


Alternatively load QuakeML or CMTSOLUTION files directly using instaseis.Source.parse() and store the sources in a list:

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sources = []

for filename in glob.iglob('data/events/quakeml/*.xml'):
sources.append(instaseis.Source.parse(filename))

print(sources[0])

for filename in glob.iglob('data/events/cmtsolutions/*'):
sources.append(instaseis.Source.parse(filename))

print(sources[0])


### 3. Extract Seismograms and Save to File¶

For the first solution using a ObsPy event catalog:

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dt = 1.0

for event in cat:
src = instaseis.Source.parse(event)
srcname = '%s_Mw_%3.1f' % (src.origin_time.date, src.moment_magnitude)
# create a usefull filename
recname = '%s_%s' % (rec.network, rec.station)
filename = '%s_%s' % (recname, srcname)
filename = filename.replace('.', '_')

# extract seismograms using instaseis

# write to miniseed files in the data_out folder. Write as MiniSEED due to multi
# component support.

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For the second solution use a list of sources:

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dt = 1.0

for src in sources:
srcname = '%s_Mw_%3.1f' % (src.origin_time.date, src.moment_magnitude)
# create a usefull filename
recname = '%s_%s' % (rec.network, rec.station)
filename = '%s_%s' % (recname, srcname)
filename = filename.replace('.', '_')

# extract seismograms using instaseis

# write to miniseed files in the data_out folder. Write as MiniSEED due to multi
# component support.

In [ ]:



Check the data:

ls data_out/